Rates of Testicular Cancer are Rising Among Racial/Ethnic Minorities

A recent study shows that testicular cancer rates are increasing for Asian/Pacific Islanders, Hispanics, and American Indians/Alaska Natives.

Testicular germ cell tumors (TGCT) are the predominant form of testicular cancer, which is the most common cancer among men between the ages of 15 and 44 years in the United States. The incidence of testicular cancer is highest among men of Northern European ancestry. A 2015 study showed that rates increased among Hispanic men between 1998 and 2011. 

“We have long known of the risk among men of Northern European ancestry, but the results of our previous study highlighted that rates were increasing among other racial/ethnic groups as well,” said Armen Ghazarian, PhD, MPH, a program director in the Division of Cancer Control and Population Sciences at the National Cancer Institute (NCI). 

A study published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research (AACR), builds on this earlier work. The 2020 study includes expanded data from across the U.S. 

“The goal was to determine if similar trends persisted in the more recent data. Monitoring trends is critical to building a better understanding of potential risk factors,” noted Katherine McGlynn, PhD, MPH, senior author on the study and a senior investigator in the Division of Cancer Epidemiology and Genetics at the NCI. 

Drs. Ghazarian and McGlynn examined TGCT incidence data from the United States Cancer Statistics public use databases. The analysis included data on cases reported between 2001 and 2016 from registries in all 50 states and the District of Columbia. 

The authors found that the incidence of TGCT was highest among non-Hispanic white men, followed by Hispanics, American Indians/Alaska Natives, Asians/Pacific Islanders, and non-Hispanic Black men. 

While the incidence of TGCT increased across all racial/ethnic groups during this period, the authors found that Asian/Pacific Islander men experienced the greatest increase, with an annual percent change (APC) of 2.47, meaning that the incidence increased by 2.47 percent each year. This was followed by Hispanics (APC 2.10), American Indians/Alaska Natives (APC 1.71), non-Hispanic blacks (APC 1.28), and non-Hispanic whites (APC 0.41). 

A 2019 study examining global trends did not find similar increases in TGCT incidence in Asian countries. 

“Given the differences in trends, it would be interesting to examine U.S. trends using data on the birthplace of Asian/Pacific Islander men, as there could be an interplay between genetic and environmental risk factors,” noted Dr. McGlynn. In her ongoing work, she aims to understand the contribution of environmental exposures, such as hormone-disrupting chemicals, on testicular cancer risk.

“I hope the results from this study will increase awareness of TGCT among men of all racial/ethnic groups,” she said. “While incidence remains highest among non-Hispanic white men, it is becoming increasingly clear that this disease does not just affect men of European ancestry.”